A group of quasi-retarded geniuses who inherit the younger generation of bass trombonists that have begun to attend the school where the older bass trombone generation currently resides. They are classified in the same way normal families are. I.e. son, father, grandson, grandfather, great grandson, Great Grand Father.

"The bass trombone family here are all retarded geniuses!"
"The best Studio here is the bass trombone families studio!"
"The new kid is coming next semester, son. Your going to be a dadddy and i'll be a grandpappy!"